If you're the parent of a teenager, you need to know the definition of this word: hornswoggle.

It means to bamboozle. To deceive by underhanded methods. To dupe.

According to Ellen Pober Rittberg, an author and mom from Roslyn, your teenagers will hornswoggle you. They will lie. They will try to throw at least one party involving "Fermented Grain Products" at a time when you aren't home. They will lead a secret life that it's your job to infiltrate.

You need to anticipate this, she says, and in her first book, "35 Things Your Teen Won't Tell You, So I Will" (Turner Publishing, $9.99), Rittberg lays out her suggested proactive tactics to help keep your children alive until age 18 and retain your own sanity until then. Rittberg, 57, also worked as a law guardian representing children in court for 13 years, so she's seen quite a bit, she says. "Worrying comes with the parent-of-a-teen turf. ... If there were a monument to parents of teens, it would consist of one massive Mount Rushmore-sized collective furrowed gray brow," she writes.

Rittberg will engage in conversation with parents of teens at the launch of her pint-size, bright orange book at 7:30 p.m. Saturday at the Book Revue in Huntington. But until then, a sampling of advice from the author and her book:

Snoop, Spy, Eavesdrop Read your teens' text messages when they're in the shower. Check their e-mail. "As for their right to privacy, I say: 'What right?'" Rittberg writes.

"Your children don't understand life, don't understand danger," Rittberg elaborates in an interview. "Their judgment is ... if not impaired, it's incomplete, and you need to know some of the things your kids are up to that can put them in harm's way. You can't have a pie-in-the-sky respect for them. They're not ready for you to confer upon them this mantle of wisdom they quite frankly don't possess."

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Some strategies she advises:

CARPOOL This accomplishes two things, Rittberg says. You get to know your children's friends, and you pick up valuable pieces of information. If you are quiet, they will forget you are there and you will overhear their gossip.

EYEBALL YOUR KIDS DAILY Establish eye contact and make sure the whites of their eyes are clear and their pupils aren't dilated. Ask them questions. "It your teens are vague and evasive, pin them down like dead butterflies," she writes.

MAKE YOUR HOUSE TEEN-FRIENDLY Translation: Provide food, TV, video games and a good stereo system so they will gather at your house rather than a local pizzeria or a deserted park.

MEET YOUR CHILDREN'S FRIENDS AND MAKE THEIR PARENTS ALLIES "Think of other parents as a network that is a combination of Interpol, the CIA, the FBI and whatever else is out there," Rittberg writes.

CARRY A PICTURE OF YOUR TEENS AS BABIES AT ALL TIMES This is for self-preservation, she says. "When your kid disappoints you, the level of disgust can be very high," Rittberg says. "When I really got disgusted with my child, I whipped out that picture." It brought back the feeling of love.

HER KIDS TURNED OUT OK

Roslyn mother Ellen Pober Rittberg has three children, grown now, who were born in the span of three years and two months, so the two boys and a girl overlapped as teens. "35 Things Your Teen Won't Tell You, So I Will" germinated then.

"Then I refined and refined it," she says. "I also wanted to write a book that was enjoyable to read, so it was funny and useful at the same time." She's been the victim of hornswoggling. In her book, she calls her children Big Boy, Middle One and the Girl. One year, when she went to visit Big Boy for parents' weekend at his college and the other two were supposed to be staying overnight with their grandmother, Middle One talked the Girl into duping their grandmother. They led her to believe each was sleeping at a friend's house; instead, they had a party and slept without an adult at Rittberg's. "For years after that, my mother called the Middle One 'the rotten kid' because he was the leader of the duplicity," Rittberg says.

"The whole thing about kids' lying, that's a really, really big one," she adds. "My daughter was president of the school, she played three sports, she was captain of the lacrosse team. And she lied. She helped throw that party. Lying just comes with the territory of being a teenager."

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Rittberg is opinionated on how the household should be run. Your role: Enlightened dictator. Benevolent despot. The boss. She is blunt about the need for forceful consequences. She doesn't think parents should buy their children cars; she thinks they should earn the money for them themselves. She thinks teens should have curfews: younger teens, between 10 and 11 on weekends; hold out at midnight for older teens for as long as you can.

As for her own three kids, Rittberg says they became responsible adults and "wonderful people." Big Boy is an attorney, Middle One is a standup comic and the Girl is a television producer and jewelry designer.